Changes in cardiopulmonary exercise capacity and limitations 3–12 months after COVID-19

Abstract

Rationale To describe cardiopulmonary function during exercise 12 months after hospital discharge for coronavirus disease 2019 (COVID-19), assess the change from 3 to 12 months, and compare the results with matched controls without COVID-19. Methods In this prospective, longitudinal, multicentre cohort study, hospitalised COVID-19 patients were examined using a cardiopulmonary exercise test (CPET) 3 and 12 months after discharge. At 3 months, 180 performed a successful CPET, and 177 did so at 12 months (mean age 59.3 years, 85 females). The COVID-19 patients were compared with controls without COVID-19 matched for age, sex, body mass index and comorbidity. Main outcome was peak oxygen uptake ( V ′ O 2 peak ). Results Exercise intolerance ( V ′ O 2 peak <80% predicted) was observed in 23% of patients at 12 months, related to circulatory (28%), ventilatory (17%) and other limitations including deconditioning and dysfunctional breathing (55%). Estimated mean difference between 3 and 12 months showed significant increases in V ′ O 2 peak % pred (5.0 percentage points (pp), 95% CI 3.1–6.9 pp; p<0.001), V ′ O 2 peak ·kg −1 % pred (3.4 pp, 95% CI 1.6–5.1 pp; p<0.001) and oxygen pulse % pred (4.6 pp, 95% CI 2.5–6.8 pp; p<0.001). V ′ O 2 peak was 2440 mL·min −1 in COVID-19 patients compared to 2972 mL·min −1 in matched controls. Conclusions 1 year after hospital discharge for COVID-19, the majority (77%), had normal exercise capacity. Only every fourth had exercise intolerance and in these circulatory limiting factors were more common than ventilator factors. Deconditioning was common. V ′ O 2 peak and oxygen pulse improved significantly from 3 months.